By doing a sim welcome-back registration or visit the topic posted here by Mr A titled "Change of 2go Phone number, Official". Always take your time aand navigate through the community and see if you can get help from other posts before you post topics like this one. To the best of my knowledge, everything you need to know about 2go has been posted by members on this site, all you need to do is to scroll carefully and you see the exploring! Enjoy.